Pluggable optical transceiver having pull-pull-tab

ABSTRACT

A pluggable optical transceiver is disclosed. The optical transceiver provides a pull-tab assembled with a body of the transceiver. The pull-tab comprises a pair of arms and a handle. The arms in an end portion thereof each provides a leg set in a guide formed in the body. Sliding the pull-tab to disengage the optical transceiver from the cage, the leg is slid within the guide to push the end portion of the arm outwardly. The handle provides in an end thereof a bar including a slope. The optical fiber pulled out from the optical connector set in the optical receptacle of the transceiver rides on the slope even when the transceiver is set in the cage by the upside-down arrangement.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. patent application Ser. No.14/172,723, filed Feb. 4, 2014, which claims the benefit of JapanesePatent Application Nos. 2013-020117, filed Feb. 5, 2013 and 2013-263886,filed Dec. 20, 2013.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present application relates to a pluggable optical transceiver, inparticular, the application relates to an optical transceiver having apull-pull-tab.

2. Background Arts

One type of optical transceivers has been well known as a pluggableoptical transceiver that is used by being temporarily and optionally setin a cage prepared in the host system. The United States PatentApplications, such as US 20030171016A and 20120148198A, have disclosedsuch a pluggable optical transceiver.

FIG. 12 illustrates a pluggable optical transceiver 100 to be set in acage 201 prepared in the host system 200. The optical transceiver 100once set in the cage 201 is unable to extract therefrom unintentionallybecause a stopper 202 provided in a side of the cage 201 prevents theoptical transceiver 100 from slipping out of the cage 201. When theoptical transceiver 100 is to be extracted from the cage, a mechanismincluding a bail 101, a slider 102, and a knob 104 prepared in a side ofthe optical transceiver 100 releases the engagement between the opticaltransceiver 100 and the cage 201. Specifically, rotating the bail 101 infront of the optical receptacle 103, the slider 102 operable with thebail 101 slides frontward as pushing the knob 104 outwardly, whichexpands the stopper 202 of the cage to release the engagement with theoptical transceiver 100. Thus, the optical transceiver 100 may be pulledout from the cage 201.

However, the slider 102 and the knob 104 of the conventional opticaltransceiver 100 have substantially no mechanisms to forbidden thelateral movement thereof. When the bail 101 receives a stress along thelateral direction of the optical transceiver 100, the slider 102 and theknob 104 easily stick out from a pocket provided in the side of theoptical transceiver where the slider 102 and the knob 104 are ordinarilyset therein. The stuck-out knob 104 has no function to expand thestopper 202 of the cage 201 outwardly; accordingly, when the opticaltransceiver 100 is set in the cage 201 with the stuck-out knob 104, theoptical transceiver 100 becomes unable to be pulled out from the cage201.

SUMMARY OF THE INVENTION

An aspect of the present application relates to an optical transceiverthat is to be inserted in a cage prepared in a host system, where thecage provides a stopper that prevents the optical transceiver fromsliding out from the cage unintentionally. The optical transceivercomprises a housing and a pull-tab. The housing encloses an opticalcomponent and an electrical component therein. Also, the housingprovides a packet and a guide formed in the pocket. The pull-tabincludes an arm and a handle integrally formed with the arm.Furthermore, the arm provides a knob and a leg in an end portionthereof, where the knob, working with a slide of the leg in the guide,expands the stopper provided in the cage when the pull-tab is pulled outto release the optical transceiver from the cage.

Further aspect of the present application relates to the pull-tab in theoptical transceiver. The handle of the pull-tab includes a pair ofextensions, each extending from the arm, and a bar connecting theextensions. A feature of the pull-tab of the present application is thatthe bar includes a supporting slope that supports an optical fiberextending from an optical connector set in an optical receptacleprovided in the optical transceiver, when the optical transceiver is setin the cage by an upside-down arrangement.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other purposes, aspects and advantages will be betterunderstood from the following detailed description of a preferredembodiment of the invention with reference to the drawings, in which:

FIG. 1 is a perspective view of an optical transceiver according to anembodiment of the present application;

FIG. 2 is an exploded view of the optical transceiver shown in FIG. 1;

FIG. 3A shows an arm at an ordinary position in the cage, and FIG. 3Bshows the arm at a position to expand the tab provided in the cage topull out the optical transceiver;

FIG. 4A shows a rear leg of the arm set in the rear guide provided inthe bottom body, and FIG. 4B shows a front leg thereof set in the frontguide;

FIG. 5A magnifies the rear portion of the arm set in the ordinaryposition thereof, and FIG. 5B shows by a cross sectional view the rearleg set in the rear guide;

FIG. 6A is a plan view of the rear guide, and FIG. 6B schematicallyshows a positional relation between the rear leg and the rear guide;

FIG. 7 is a perspective view of a modified arm;

FIG. 8 shows a modified rear guide provided in the top body to receivethe modified arm shown in FIG. 7;

FIG. 9 is a perspective view of the handle according to an embodiment;

FIG. 10 shows an optical transceiver set in the cage by the upside-downarrangement;

FIG. 11A is a side view of the optical transceiver set in the cage bythe upside-down arrangement, and FIG. 11B magnifies the front endportion of the handle to receive the optical fiber; and

FIG. 12 is a perspective view of an optical transceiver without apull-tab, where the optical transceiver is to be set within the cage.

DESCRIPTION OF EMBODIMENTS

Next, some embodiments according to the present application will bedescribed as referring to drawings. In the description of the drawings,numerals or symbols same or similar to each other will refer to elementssame or similar to each other without duplicated explanations.

FIG. 1 is an outer appearance of an optical transceiver 1 of anembodiment. The optical transceiver 1 is a type of, what is called, thepluggable optical transceiver plugged in a host system without turningoff the power of the host system. Accordingly, the optical transceiveris sometimes called as the type of the hot-pluggable opticaltransceiver. The optical transceiver 1 includes transducers to transducesignals between electrical and optical signals, and a circuit board formounting electrical components thereon, where they are enclosed within ahousing 3. The housing 3 comprises a top body 4 and a bottom body 5providing a space where those optical and electrical components areenclosed therein. The top and bottom bodies, 4 and 5, are made of metal,preferably die-casted aluminum and die-casted zinc; but resin-madebodies are applicable to the optical transceiver 1.

The transducers, where they are not explicitly illustrated in thefigures, includes a transmitter optical subassembly (TOSA) to convert anelectrical signal provided from the host system into an optical signaloutput to an external fiber; and a receiver optical subassembly (ROSA)to convert an optical signal provided from an optical fiber into anelectrical signal output to the host system. The TOSA installs alight-emitting device, typically a semiconductor laser diode (LD);while, the ROSA installs a light-receiving device, typically aphotodiode (PD), where the TOSA and the ROSA, or the LD and the PD, areelectrically coupled with respective electronic circuits mounted on thecircuit board. One of electrical circuits drives the LD, while, theother processes the signal output from the PD. The circuit boardprovides an electrical plug 2 in a rear end thereof, where theelectrical plug 2 is to be mated with an electrical connector preparedin the host system 200 to communicate the optical transceiver 1 with thehost system 200.

The optical transceiver 1 of the present embodiment further provides apull-tab 8 including a pair of metal arms 7 and a handle 6 made of resinand integrally formed with the arms 7. Details of the arms 7 and thehandle 6 will be described later.

FIG. 2 is an exploded view of the optical transceiver 1, where opticaland electrical components enclosed in the housing 3 are omitted. The topbody 4 provides an optical receptacle 41 in the front end thereof.Directions, such as front, rear, top, and/or bottom, are used merely toexplain the arrangements and do not restrict the scope of the invention.The front corresponds to a side where the optical receptacle 41 isprovided; while, the rear is merely opposite to the front. The top onlycorresponds to a side where the top body 4 is provided, and the bottomis opposite thereto.

Mating an external connector with the optical receptacle 41, the LD andthe PD in the TOSA and the ROSA, respectively, optically couple with theexternal fiber secured in the external connector. As shown in FIGS. 1and 2, the optical receptacle 41 provides two ports each correspondingto the TOSA and the ROSA; thus, the optical transceiver 1 of theembodiment realizes the full duplex optical communication. The top body4 provides sides 42 that include a pocket 43, a smooth surface 44, and aslope 45 connecting the smooth surface 44 to the pocket 43. The pocket43 receives the stopper 202 of the cage 200 to latch the opticaltransceiver 1 in the cage 200 and an end portion of the arm 7; while,the smooth surface 44 faces the arm 7.

The bottom body 5 provides a front guide 51 and a rear guide 52 eachreceiving the front leg 72 and the rear leg 73 of the arm 7. The bottombody 5 is fastened with the top body 4 by the fitting in the rear but bythe screws 9 in the front. The handle 6 is for pulling the opticaltransceiver 1 out from the cage 201, in particular, when the opticaltransceivers 1 with the configuration shown in the figures are denselyinstalled on the host system, an optical transceiver 1 is hard to bepicked in the front thereof to release from the host system. The handle6 may facilitate the releasing of the optical transceiver 1 from thecage 201. The handle 6 provides a bar 62 to facilitate the manualpicking.

The arm 7 extends from the rear end of the handle 6. A span between thearms 7 is slightly wider than a width of the handle 6, but tapered in arear 74 thereof. Moreover, the arm 7 provides a knob 71 in the rear endthereof. The knob 71 has a U-shaped cross section as facing the bottomof the U-character outwardly. The knob 71, when the transceiver 1 is setin the cage 202, is set in the pocket 43 of the top boy 4 such that thebottom of the U-shape does not protrude from the side of the housing 3.The knob 71 pushes the stopper 202 of the cage 201 outwardly todisengage the stopper 202 with the pocket 43. Setting the legs, 72 and73, within respective guides, 51 and 52, provided in the bottom body 5,the pull-tab 8 is assembled with the top and bottom bodies, 4 and 5.

A releasing mechanism of the optical transceiver 1 from the cage 201will be described as referring to FIGS. 3 and 4. FIG. 3A illustrates astate where the pull-tab 8, or the arm 7, is in the position where theoptical transceiver 1 is set in the cage 201, namely, the stopper 202 ofthe cage 201 engages with the optical transceiver 1; while, FIG. 3Billustrates a state where the optical transceiver 1 is free from thestopper 202 of the cage 201. FIG. 4A omits the top body 4 from FIG. 3A,and FIG. 4B magnifies a portion of front leg 51, where FIG. 4B is afragmentally sectional view.

When the optical transceiver 1 is set in the cage 201, that is, a statewhere the pull-tab 8 is not pulled to slide the arm 7 on the smoothsurface 44; the knob 71 is set in the pocket 43 of the top body 4 suchthat the knob 71 does not protrude from the side 42 as shown in FIG. 3A.The stopper 202 of the cage 201 abuts against the rear wall 43 a of thepocket 43 such that the optical transceiver 1 is not released from thecage 201.

Pulling the handle 6 forwardly, which slides the arm 7, the rear portion74 of the arm 7 including the knob 71 slides on the slope 45 to push therear portion 74 outwardly. Because the rear leg 73 is set in the rearguide 52, an upper side of the rear portion 74 of the arm 7 is pushedoutwardly by the sliding but a lower side thereof is still set in therear guide 52; that is, the mechanism of the rear leg 73 and the rearguide 52 causes a twisted deformation in the rear portion 74 of the arm7, which facilitates the disengagement of the stopper 202 in the cage201 from the rear wall 43 a of the pocket 43.

Further pulling the handle 6 frontward, the rear leg 73 in the front end73 a thereof comes in contact with the front wall 52 a of the rear guide52, as shown in FIG. 4A, and the front leg 72 in the front portion 72 acomes in contact with the front wall 51 a of the front guide 51. In thisstate of the legs, 72 and 73, and the guides, 51 and 52, the knob 71fully pushes the stopper 202 outwardly, and the optical transceiver 1 isfree from the stopper 202. Still further pulling the handle 6 frontward,the optical transceiver 1 is pulled out from the cage 201. Oppositely,when the optical transceiver 1 is inserted into the cage 201, the rearend of the rear leg 73 abuts against the rear wall 52 c of the rearguide 52 to push the optical transceiver 1 rearward. Thus, the frontguide 51 and the rear guide 52 have a length enough for the legs, 72 and73, to slide therein to push the stopper 202 outwardly.

In the state where the end portion 74 of the arm 7 is set within thepocket 43, the knob 71 or the end portion 74 of the arm 7 is preventedfrom pushing the stopper 202 of the cage 201 outwardly; because the rearleg 73 is set in the rear guide 52 and the outer side 73 b of the rearleg 73 abuts against the inner side 52 b of the rear guide 52, as shownin FIGS. 5A and 5B. FIG. 5A magnifies a state when the rear end portion74 of the arm 7 is set in the pocket 43 such that the rear leg 73 is inthe rear guide 52, and FIG. 5B shows the cross section of the arm 7, andthe top and bottom bodies, 4 and 5. FIG. 7A is a plan view of the rearguide 52 and FIG. 7B shows a positional relation between the rear guide52 and the rear leg 73.

The arm 7 in the rear end portion 74 thereof is prevented from extrudingoutwardly even when the optical receptacle 41 receives a lateral stressbecause the rear guide 52 prevents the rear leg 73 from expandingoutward. Thus, the arm 7 in the rear end portion 74 thereof isprohibited from protruding from the housing 3 except for the operationto disengage the optical transceiver 1 from the cage 201; accordingly,the optical transceiver 1 is securely engaged with the cage 201.

Another embodiment of the present application will be described asreferring to FIGS. 7 and 8. FIG. 7 illustrates a handle 6 accompaniedwith an arms 7A modified from those 7 shown in the FIGS. 1 to 6, while,FIG. 8 magnifies an inside of the top body 4B modified from theaforementioned body 4.

The modified arm 7A also provides the front leg 72 and rear leg 73A butthe position thereof in the arm 7A is diagonal against the position ofthe front leg 72. Also, the top body 4 is modified to another top body4A shown in FIG. 8. Specifically, the modified top body 4A provides therear guide 46 that receives the rear leg 73A. Also, the height of theside 42A of the top body 4 is lowered, instead, that of the lower body 5is enhanced. That is, a portion of the side 42 of the top body 4 istransferred to the bottom body 5. Concurrently with the arrangementabove, the smooth surface 44A, the slope 45A, and the pocket 43A aredivided into two parts, one of which is provided in the top body 4A,while, the other part is provided in the bottom body 5.

In the optical transceiver of the modified embodiment, when the rear leg73A receives a lateral force to push the arm 7A outwardly, the outsidesurface 73Ab of the leg 73A abuts against the inside surface 46 a of therear guide 46 in the top body 4A, which prevents the rear leg 73A fromprotruding from the side of the top body 4A. The end portion 74 of thearm 7A is stably set in the side of the housing 3 except for the actionto disengage the optical transceiver 1 from the cage 201.

An arrangement of the handle 6 will be further described. When the hostsystem 200 densely mounts optical transceivers like those shown in FIG.1 and the optical transceivers have no handles 6, theengagement/disengagement of the optical transceiver 1 with respect tothe cage 201 becomes hard because the optical transceivers are unable tomanipulate manually. In such a case, the handle 6 shown in the figuresbecomes effective. However, the bar 62 provided in the front end of thehandle 6 sometimes interferes with the extension of the optical fiber11. In particular, when the optical transceiver 1 is set in the cage by,what is called, the belly to belly arrangement or in the upside-downarrangement.

When the optical transceiver 1 is set in the cage by an ordinaryarrangement, that is, the pull-tab 6 is set in the upper of the opticalreceptacle 41, the external fiber 11 extending from the opticalconnector 12 set in the optical receptacle 41 naturally droops from theend of the boot secured in the optical connector 12 by a radius of acurvature at least 30 mm without being interfered with the bar 62 of thehandle 6. However, when an optical transceiver 1 is set in the cage bythe upside-down arrangement, where the handle 6 of the pull-tab 8extends from the bottom side of the optical receptacle 42, the bar 62occasionally interferes with the extension of the external fiber. Theexternal fiber extracted from the optical connector sometimes runs onthe bar 62, and receives a stress from an edge of the bar 62. In such anarrangement, the optical fiber 11 sometimes bends at the edge of the bar62 by a radius less than 30 mm, which is one of thresholds to compensatefor the bend loss of the fiber. The pull-tab 8 according to anembodiment of the present application provides a mechanism to releasethe stress affecting the optical fiber 11 from the bar 62.

FIG. 9 shows a detail of the pull-tab 8 from the bottom side of theoptical transceiver 1, where the optical transceiver 1 is set in thecage in the upside-down arrangement. The pull-tab 8, similar to thoseshown in FIGS. 1 to 7, provides the handle 6 and the arm 7. The handle 6comprises a pair of extensions 61 extending forwardly from a portion ofthe optical receptacle 41, and the bar 62 connecting the extensions 61in the front of the handle 6. The bar 62 in a front end 63 thereof isformed in an arched shape to facilitate the manipulating of the handle 6manually at the insertion/extraction of the optical transceiver 1 withrespect to the cage 201.

The bar 62 further provides a supporting surface 64 making a substantialangle with respect to the optical axis of the optical receptacle 41. Thesupporting surface 64 puts the optical fiber 11 extending from theoptical connector thereon. Accordingly, the supporting surface 64 has aconvex surface with a radius of the curvature thereof greater than 30mm, which satisfies a standard of, for instance, ITU-TG.652 concerningto the bend loss of a single mode fiber for the general purpose.

The bar 62 also provides walls 65 in both sides of the supportingsurface 64 to guide the optical fiber 11. Thus, the bar 62 according tothe present embodiment provides a pocket formed by two walls 65 and thesupporting surface 64 to set the optical fiber 11 therein. Moreover, thesupporting surface 64 has the convex surface with the predeterminedradius. This arrangement of the bar 62 releases the optical fiber 11from receiving an undesired stress even when the optical fiber 11 isdrawn from the optical receptacle 42 and naturally droops downwardly. Aconventional bar has a shape similar to those shown in FIG. 9, namely,combining respective extensions 61; but the supporting surface 64 isfilled with a resin forming the handle 6. The fiber 11 extending fromthe optical receptacle 41 often rides on the bar 62, then droopsdownwardly, which sometimes forces the optical fiber 11 to bend at theedge of the bar 62 by a radius less than 30 mm. The optical fiber 11 ofthe present embodiment is released from being interfered with the bar62; moreover, even when the optical fiber 11 rides on the bar 62, thecurvature of the supporting surface 64 prevents the optical fiber 11from being bent by a radius less than 30 mm.

FIG. 10 shows an optical transceiver 1 set in the cage 201A in theupside-down arrangement, namely, the handle 6 extends from the lowerside of the optical receptacle 41 and the optical fiber 11 rides on thesupporting surface 64 in the bar 62. FIG. 10 omits another opticaltransceiver set in the cage 201A above the one shown in FIG. 10, wheretwo optical transceivers are set in the cage 201 in the belly to bellyarrangement. FIG. 11A is a side view when the optical transceiver 1 inthe upside-down arrangement receives an optical connector 12 in theoptical receptacle 41; while, FIG. 11B to shows a cross section of aportion of the supporting surface 64 where the optical fiber 11 ridesthereon. The optical connector 12 extends a boot 13 with a preset lengthto protect the optical fiber set therein. The optical fiber 11 extendingfrom the boot 13 comes in contact to the supporting surface 64 at leasttwo points, then droops downwardly at the edge of the supporting surface64.

In order to manipulate the handle 6 to insert/extract the opticaltransceiver 1, the handle 6 is preferably to protrude from the end ofthe boot 13. Even when such an arrangement of the handle 6, exactly, thebar 62, does not interfere with the optical fiber 11 when the opticaltransceiver 1 is set in the cage 201A by the normal posture, because theoptical fiber 11 naturally droops at the end of the boot 13. On theother hand, when the optical transceiver 1 is set in the cage 201A bythe upside-down arrangement, the bar 62 could interfere with theextension of the optical fiber 11. Some countermeasures against theminimum bending radius may be necessary.

Referring to FIG. 11B, the bar 62 of the present embodiment has afeature that the end point ‘a’ of the boot 13, the end points, ‘b’ and‘c’, of the supporting surface 64 form an arch with a radii of thecurvature thereof greater than 30 mm. The optical fiber 11 pulled outfrom the optical connector 12 droops at the end point ‘a’ of the boot 13by the radius of 30 mm. That is, the extensions 61 of the handle 6 has alength with respect to the dimensions of the optical connector 12, inparticular, to the end of the boot 13, such that the end ‘a’ of the boot13 and two points, ‘b’ and ‘c’ of the supporting surface 64 are on thearch with the radius of 30 mm or larger.

In the foregoing detailed description, the method and apparatus of thepresent invention have been described with reference to specificexemplary embodiments thereof. It will, however, be evident that variousmodifications and changes may be made thereto without departing from thebroader spirit and scope of the present invention. The presentspecification and figures are accordingly to be regarded as illustrativerather than restrictive.

What is claimed is:
 1. An optical transceiver to be inserted in a cageprepared in a host system, the cage providing a stopper to prevent theoptical transceiver from sliding out therefrom, the optical transceivercomprising: a housing configured to enclose an optical component and anelectrical component therein; an optical receptacle that receives anexternal optical connector therein; and a pull-tab including a handlehaving a pair of extensions and a bar connecting the extensions, the barincluding a supporting slope that supports an optical fiber extendingfrom the optical connector set in the optical receptacle, wherein theoptical fiber is secured with a boot from an end of the external opticalconnector, and wherein the boot in an end thereof, the supporting slopein an end closest to the optical transceiver, and another end of thesupporting slope farthest from the optical transceiver virtually form anarch with a radius of curvature greater than 30 mm.
 2. The opticaltransceiver of claim 1, wherein the supporting slope supports theoptical fiber when the optical transceiver is set in the cage by anupside-down arrangement.
 3. The optical transceiver of claim 1, whereinthe bar further provides walls in respective sides thereof, the wallsand supporting slope forming a hollow that secures the optical fibertherein.
 4. The optical transceiver of claim 1, wherein the bar providesa front end thereof formed in an arched shape.